xref: /freebsd/sys/dev/uart/uart_tty.c (revision 7773002178c8dbc52b44e4d705f07706409af8e4)
1 /*
2  * Copyright (c) 2003 Marcel Moolenaar
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/conf.h>
34 #include <sys/cons.h>
35 #include <sys/fcntl.h>
36 #include <sys/interrupt.h>
37 #include <sys/kernel.h>
38 #include <sys/malloc.h>
39 #include <sys/reboot.h>
40 #include <machine/bus.h>
41 #include <sys/rman.h>
42 #include <sys/termios.h>
43 #include <sys/tty.h>
44 #include <machine/resource.h>
45 #include <machine/stdarg.h>
46 
47 #include <dev/uart/uart.h>
48 #include <dev/uart/uart_bus.h>
49 #include <dev/uart/uart_cpu.h>
50 
51 #include "uart_if.h"
52 
53 #define	UART_MINOR_CALLOUT	0x10000
54 
55 static cn_probe_t uart_cnprobe;
56 static cn_init_t uart_cninit;
57 static cn_term_t uart_cnterm;
58 static cn_getc_t uart_cngetc;
59 static cn_checkc_t uart_cncheckc;
60 static cn_putc_t uart_cnputc;
61 
62 CONS_DRIVER(uart, uart_cnprobe, uart_cninit, uart_cnterm, uart_cngetc,
63     uart_cncheckc, uart_cnputc, NULL);
64 
65 static d_open_t uart_tty_open;
66 static d_close_t uart_tty_close;
67 static d_ioctl_t uart_tty_ioctl;
68 
69 static struct cdevsw uart_cdevsw = {
70 	.d_open = uart_tty_open,
71 	.d_close = uart_tty_close,
72 	.d_read = ttyread,
73 	.d_write = ttywrite,
74 	.d_ioctl = uart_tty_ioctl,
75 	.d_poll = ttypoll,
76 	.d_name = uart_driver_name,
77 	.d_flags = D_TTY,
78 	.d_kqfilter = ttykqfilter,
79 };
80 
81 static struct uart_devinfo uart_console;
82 
83 static void
84 uart_cnprobe(struct consdev *cp)
85 {
86 
87 	cp->cn_pri = CN_DEAD;
88 
89 	KASSERT(uart_console.cookie == NULL, ("foo"));
90 
91 	if (uart_cpu_getdev(UART_DEV_CONSOLE, &uart_console))
92 		return;
93 
94 	if (uart_probe(&uart_console))
95 		return;
96 
97 	cp->cn_pri = (boothowto & RB_SERIAL) ? CN_REMOTE : CN_NORMAL;
98 	cp->cn_arg = &uart_console;
99 }
100 
101 static void
102 uart_cninit(struct consdev *cp)
103 {
104 	struct uart_devinfo *di;
105 
106 	/*
107 	 * Yedi trick: we need to be able to define cn_dev before we go
108 	 * single- or multi-user. The problem is that we don't know at
109 	 * this time what the device will be. Hence, we need to link from
110 	 * the uart_devinfo to the consdev that corresponds to it so that
111 	 * we can define cn_dev in uart_bus_attach() when we find the
112 	 * device during bus enumeration. That's when we'll know what the
113 	 * the unit number will be.
114 	 */
115 	di = cp->cn_arg;
116 	KASSERT(di->cookie == NULL, ("foo"));
117 	di->cookie = cp;
118 	di->type = UART_DEV_CONSOLE;
119 	uart_add_sysdev(di);
120 	uart_init(di);
121 }
122 
123 static void
124 uart_cnterm(struct consdev *cp)
125 {
126 
127 	uart_term(cp->cn_arg);
128 }
129 
130 static void
131 uart_cnputc(struct consdev *cp, int c)
132 {
133 
134 	uart_putc(cp->cn_arg, c);
135 }
136 
137 static int
138 uart_cncheckc(struct consdev *cp)
139 {
140 
141 	return (uart_poll(cp->cn_arg));
142 }
143 
144 static int
145 uart_cngetc(struct consdev *cp)
146 {
147 
148 	return (uart_getc(cp->cn_arg));
149 }
150 
151 static void
152 uart_tty_oproc(struct tty *tp)
153 {
154 	struct uart_softc *sc;
155 
156 	KASSERT(tp->t_dev != NULL, ("foo"));
157 	sc = tp->t_dev->si_drv1;
158 	if (sc == NULL || sc->sc_leaving)
159 		return;
160 
161 	/*
162 	 * Handle input flow control. Note that if we have hardware support,
163 	 * we don't do anything here. We continue to receive until our buffer
164 	 * is full. At that time we cannot empty the UART itself and it will
165 	 * de-assert RTS for us. In that situation we're completely stuffed.
166 	 * Without hardware support, we need to toggle RTS ourselves.
167 	 */
168 	if ((tp->t_cflag & CRTS_IFLOW) && !sc->sc_hwiflow) {
169 		if ((tp->t_state & TS_TBLOCK) &&
170 		    (sc->sc_hwsig & UART_SIG_RTS))
171 			UART_SETSIG(sc, UART_SIG_DRTS);
172 		else if (!(tp->t_state & TS_TBLOCK) &&
173 		    !(sc->sc_hwsig & UART_SIG_RTS))
174 			UART_SETSIG(sc, UART_SIG_DRTS|UART_SIG_RTS);
175 	}
176 
177 	if (tp->t_state & TS_TTSTOP)
178 		return;
179 
180 	if ((tp->t_state & TS_BUSY) || sc->sc_txbusy)
181 		return;
182 
183 	if (tp->t_outq.c_cc == 0) {
184 		ttwwakeup(tp);
185 		return;
186 	}
187 
188 	sc->sc_txdatasz = q_to_b(&tp->t_outq, sc->sc_txbuf, sc->sc_txfifosz);
189 	tp->t_state |= TS_BUSY;
190 	UART_TRANSMIT(sc);
191 	ttwwakeup(tp);
192 }
193 
194 static int
195 uart_tty_param(struct tty *tp, struct termios *t)
196 {
197 	struct uart_softc *sc;
198 	int databits, parity, stopbits;
199 
200 	KASSERT(tp->t_dev != NULL, ("foo"));
201 	sc = tp->t_dev->si_drv1;
202 	if (sc == NULL || sc->sc_leaving)
203 		return (ENODEV);
204 	if (t->c_ispeed != t->c_ospeed && t->c_ospeed != 0)
205 		return (EINVAL);
206 	/* Fixate certain parameters for system devices. */
207 	if (sc->sc_sysdev != NULL) {
208 		t->c_ispeed = t->c_ospeed = sc->sc_sysdev->baudrate;
209 		t->c_cflag |= CLOCAL;
210 		t->c_cflag &= ~HUPCL;
211 	}
212 	if (t->c_ospeed == 0) {
213 		UART_SETSIG(sc, UART_SIG_DDTR | UART_SIG_DRTS);
214 		return (0);
215 	}
216 	switch (t->c_cflag & CSIZE) {
217 	case CS5:	databits = 5; break;
218 	case CS6:	databits = 6; break;
219 	case CS7:	databits = 7; break;
220 	default:	databits = 8; break;
221 	}
222 	stopbits = (t->c_cflag & CSTOPB) ? 2 : 1;
223 	if (t->c_cflag & PARENB)
224 		parity = (t->c_cflag & PARODD) ? UART_PARITY_ODD
225 		    : UART_PARITY_EVEN;
226 	else
227 		parity = UART_PARITY_NONE;
228 	UART_PARAM(sc, t->c_ospeed, databits, stopbits, parity);
229 	UART_SETSIG(sc, UART_SIG_DDTR | UART_SIG_DTR);
230 	/* Set input flow control state. */
231 	if (!sc->sc_hwiflow) {
232 		if ((t->c_cflag & CRTS_IFLOW) && (tp->t_state & TS_TBLOCK))
233 			UART_SETSIG(sc, UART_SIG_DRTS);
234 		else
235 			UART_SETSIG(sc, UART_SIG_DRTS | UART_SIG_RTS);
236 	} else
237 		UART_IOCTL(sc, UART_IOCTL_IFLOW, (t->c_cflag & CRTS_IFLOW));
238 	/* Set output flow control state. */
239 	if (sc->sc_hwoflow)
240 		UART_IOCTL(sc, UART_IOCTL_OFLOW, (t->c_cflag & CCTS_OFLOW));
241 	ttsetwater(tp);
242 	return (0);
243 }
244 
245 static void
246 uart_tty_stop(struct tty *tp, int rw)
247 {
248 	struct uart_softc *sc;
249 
250 	KASSERT(tp->t_dev != NULL, ("foo"));
251 	sc = tp->t_dev->si_drv1;
252 	if (sc == NULL || sc->sc_leaving)
253 		return;
254 	if (rw & FWRITE) {
255 		if (sc->sc_txbusy) {
256 			sc->sc_txbusy = 0;
257 			UART_FLUSH(sc, UART_FLUSH_TRANSMITTER);
258 		}
259 		tp->t_state &= ~TS_BUSY;
260 	}
261 	if (rw & FREAD) {
262 		UART_FLUSH(sc, UART_FLUSH_RECEIVER);
263 		sc->sc_rxget = sc->sc_rxput = 0;
264 	}
265 }
266 
267 void
268 uart_tty_intr(void *arg)
269 {
270 	struct uart_softc *sc = arg;
271 	struct tty *tp;
272 	int c, pend, sig, xc;
273 
274 	if (sc->sc_leaving)
275 		return;
276 
277 	pend = atomic_readandclear_32(&sc->sc_ttypend);
278 	if (!(pend & UART_IPEND_MASK))
279 		return;
280 
281 	tp = sc->sc_u.u_tty.tp;
282 
283 	if (pend & UART_IPEND_RXREADY) {
284 		while (!uart_rx_empty(sc) && !(tp->t_state & TS_TBLOCK)) {
285 			xc = uart_rx_get(sc);
286 			c = xc & 0xff;
287 			if (xc & UART_STAT_FRAMERR)
288 				c |= TTY_FE;
289 			if (xc & UART_STAT_PARERR)
290 				c |= TTY_PE;
291 			(*linesw[tp->t_line].l_rint)(c, tp);
292 		}
293 	}
294 
295 	if (pend & UART_IPEND_BREAK) {
296 		if (tp != NULL && !(tp->t_iflag & IGNBRK))
297 			(*linesw[tp->t_line].l_rint)(0, tp);
298 	}
299 
300 	if (pend & UART_IPEND_SIGCHG) {
301 		sig = pend & UART_IPEND_SIGMASK;
302 		if (sig & UART_SIG_DDCD)
303 			(*linesw[tp->t_line].l_modem)(tp, sig & UART_SIG_DCD);
304 		if ((sig & UART_SIG_DCTS) && (tp->t_cflag & CCTS_OFLOW) &&
305 		    !sc->sc_hwoflow) {
306 			if (sig & UART_SIG_CTS) {
307 				tp->t_state &= ~TS_TTSTOP;
308 				(*linesw[tp->t_line].l_start)(tp);
309 			} else
310 				tp->t_state |= TS_TTSTOP;
311 		}
312 	}
313 
314 	if (pend & UART_IPEND_TXIDLE) {
315 		tp->t_state &= ~TS_BUSY;
316 		(*linesw[tp->t_line].l_start)(tp);
317 	}
318 }
319 
320 int
321 uart_tty_attach(struct uart_softc *sc)
322 {
323 	struct tty *tp;
324 
325 	tp = ttymalloc(NULL);
326 	sc->sc_u.u_tty.tp = tp;
327 
328 	sc->sc_u.u_tty.si[0] = make_dev(&uart_cdevsw,
329 	    device_get_unit(sc->sc_dev), UID_ROOT, GID_WHEEL, 0600, "ttyu%r",
330 	    device_get_unit(sc->sc_dev));
331 	sc->sc_u.u_tty.si[0]->si_drv1 = sc;
332 	sc->sc_u.u_tty.si[0]->si_tty = tp;
333 	sc->sc_u.u_tty.si[1] = make_dev(&uart_cdevsw,
334 	    device_get_unit(sc->sc_dev) | UART_MINOR_CALLOUT, UID_UUCP,
335 	    GID_DIALER, 0660, "uart%r", device_get_unit(sc->sc_dev));
336 	sc->sc_u.u_tty.si[1]->si_drv1 = sc;
337 	sc->sc_u.u_tty.si[1]->si_tty = tp;
338 
339 	tp->t_oproc = uart_tty_oproc;
340 	tp->t_param = uart_tty_param;
341 	tp->t_stop = uart_tty_stop;
342 
343 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
344 		sprintf(((struct consdev *)sc->sc_sysdev->cookie)->cn_name,
345 		    "ttyu%r", device_get_unit(sc->sc_dev));
346 	}
347 
348 	swi_add(&tty_ithd, uart_driver_name, uart_tty_intr, sc, SWI_TTY,
349 	    INTR_TYPE_TTY, &sc->sc_softih);
350 
351 	return (0);
352 }
353 
354 int uart_tty_detach(struct uart_softc *sc)
355 {
356 
357 	ithread_remove_handler(sc->sc_softih);
358 	destroy_dev(sc->sc_u.u_tty.si[0]);
359 	destroy_dev(sc->sc_u.u_tty.si[1]);
360 	/* ttyfree(sc->sc_u.u_tty.tp); */
361 
362 	return (0);
363 }
364 
365 static int
366 uart_tty_open(dev_t dev, int flags, int mode, struct thread *td)
367 {
368 	struct uart_softc *sc;
369 	struct tty *tp;
370 	int error;
371 
372 	sc = dev->si_drv1;
373 	if (sc == NULL || sc->sc_leaving)
374 		return (ENODEV);
375 
376 	tp = dev->si_tty;
377 
378  loop:
379 	if (sc->sc_opened) {
380 		KASSERT(tp->t_state & TS_ISOPEN, ("foo"));
381 		/*
382 		 * The device is open, so everything has been initialized.
383 		 * Handle conflicts.
384 		 */
385 		if (minor(dev) & UART_MINOR_CALLOUT) {
386 			if (!sc->sc_callout)
387 				return (EBUSY);
388 		} else {
389 			if (sc->sc_callout) {
390 				if (flags & O_NONBLOCK)
391 					return (EBUSY);
392 				error =	tsleep(sc, TTIPRI|PCATCH, "uartbi", 0);
393 				if (error)
394 					return (error);
395 				sc = dev->si_drv1;
396 				if (sc == NULL || sc->sc_leaving)
397 					return (ENODEV);
398 				goto loop;
399 			}
400 		}
401 		if (tp->t_state & TS_XCLUDE && suser(td) != 0)
402 			return (EBUSY);
403 	} else {
404 		KASSERT(!(tp->t_state & TS_ISOPEN), ("foo"));
405 		/*
406 		 * The device isn't open, so there are no conflicts.
407 		 * Initialize it.  Initialization is done twice in many
408 		 * cases: to preempt sleeping callin opens if we are
409 		 * callout, and to complete a callin open after DCD rises.
410 		 */
411 		sc->sc_callout = (minor(dev) & UART_MINOR_CALLOUT) ? 1 : 0;
412 		tp->t_dev = dev;
413 
414 		tp->t_cflag = TTYDEF_CFLAG;
415 		tp->t_iflag = TTYDEF_IFLAG;
416 		tp->t_lflag = TTYDEF_LFLAG;
417 		tp->t_oflag = TTYDEF_OFLAG;
418 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
419 		ttychars(tp);
420 		error = uart_tty_param(tp, &tp->t_termios);
421 		if (error)
422 			return (error);
423 		/*
424 		 * Handle initial DCD.
425 		 */
426 		if ((sc->sc_hwsig & UART_SIG_DCD) || sc->sc_callout)
427 			(*linesw[tp->t_line].l_modem)(tp, 1);
428 	}
429 	/*
430 	 * Wait for DCD if necessary.
431 	 */
432 	if (!(tp->t_state & TS_CARR_ON) && !sc->sc_callout &&
433 	    !(tp->t_cflag & CLOCAL) && !(flags & O_NONBLOCK)) {
434 		error = tsleep(TSA_CARR_ON(tp), TTIPRI|PCATCH, "uartdcd", 0);
435 		if (error)
436 			return (error);
437 		sc = dev->si_drv1;
438 		if (sc == NULL || sc->sc_leaving)
439 			return (ENODEV);
440 		goto loop;
441 	}
442 	error = ttyopen(dev, tp);
443 	if (error)
444 		return (error);
445 	error = (*linesw[tp->t_line].l_open)(dev, tp);
446 	if (error)
447 		return (error);
448 
449 	KASSERT(tp->t_state & TS_ISOPEN, ("foo"));
450 	sc->sc_opened = 1;
451 	return (0);
452 }
453 
454 static int
455 uart_tty_close(dev_t dev, int flags, int mode, struct thread *td)
456 {
457 	struct uart_softc *sc;
458 	struct tty *tp;
459 
460 	sc = dev->si_drv1;
461 	if (sc == NULL || sc->sc_leaving)
462 		return (ENODEV);
463 	tp = dev->si_tty;
464 	if (!sc->sc_opened) {
465 		KASSERT(!(tp->t_state & TS_ISOPEN), ("foo"));
466 		return (0);
467 	}
468 	KASSERT(tp->t_state & TS_ISOPEN, ("foo"));
469 
470 	if (sc->sc_hwiflow)
471 		UART_IOCTL(sc, UART_IOCTL_IFLOW, 0);
472 	if (sc->sc_hwoflow)
473 		UART_IOCTL(sc, UART_IOCTL_OFLOW, 0);
474 	if (sc->sc_sysdev == NULL)
475 		UART_SETSIG(sc, UART_SIG_DDTR | UART_SIG_DRTS);
476 
477 	/* Disable pulse capturing. */
478 	sc->sc_pps.ppsparam.mode = 0;
479 
480 	(*linesw[tp->t_line].l_close)(tp, flags);
481 	ttyclose(tp);
482 	wakeup(sc);
483 	wakeup(TSA_CARR_ON(tp));
484 	KASSERT(!(tp->t_state & TS_ISOPEN), ("foo"));
485 	sc->sc_opened = 0;
486 	return (0);
487 }
488 
489 static int
490 uart_tty_ioctl(dev_t dev, u_long cmd, caddr_t data, int flags,
491     struct thread *td)
492 {
493 	struct uart_softc *sc;
494 	struct tty *tp;
495 	int bits, error, sig;
496 
497 	sc = dev->si_drv1;
498 	if (sc == NULL || sc->sc_leaving)
499 		return (ENODEV);
500 
501 	tp = dev->si_tty;
502 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flags, td);
503 	if (error != ENOIOCTL)
504 		return (error);
505 	error = ttioctl(tp, cmd, data, flags);
506 	if (error != ENOIOCTL)
507 		return (error);
508 
509 	error = 0;
510 	switch (cmd) {
511 	case TIOCSBRK:
512 		UART_IOCTL(sc, UART_IOCTL_BREAK, 1);
513 		break;
514 	case TIOCCBRK:
515 		UART_IOCTL(sc, UART_IOCTL_BREAK, 0);
516 		break;
517 	case TIOCSDTR:
518 		UART_SETSIG(sc, UART_SIG_DDTR | UART_SIG_DTR);
519 		break;
520 	case TIOCCDTR:
521 		UART_SETSIG(sc, UART_SIG_DDTR);
522 		break;
523 	case TIOCMSET:
524 		bits = *(int*)data;
525 		sig = UART_SIG_DDTR | UART_SIG_DRTS;
526 		if (bits & TIOCM_DTR)
527 			sig |= UART_SIG_DTR;
528 		if (bits & TIOCM_RTS)
529 			sig |= UART_SIG_RTS;
530 		UART_SETSIG(sc, sig);
531 		break;
532         case TIOCMBIS:
533 		bits = *(int*)data;
534 		sig = 0;
535 		if (bits & TIOCM_DTR)
536 			sig |= UART_SIG_DDTR | UART_SIG_DTR;
537 		if (bits & TIOCM_RTS)
538 			sig |= UART_SIG_DRTS | UART_SIG_RTS;
539 		UART_SETSIG(sc, sig);
540 		break;
541         case TIOCMBIC:
542 		bits = *(int*)data;
543 		sig = 0;
544 		if (bits & TIOCM_DTR)
545 			sig |= UART_SIG_DDTR;
546 		if (bits & TIOCM_RTS)
547 			sig |= UART_SIG_DRTS;
548 		UART_SETSIG(sc, sig);
549 		break;
550         case TIOCMGET:
551 		sig = sc->sc_hwsig;
552 		bits = TIOCM_LE;
553 		if (sig & UART_SIG_DTR)
554 			bits |= TIOCM_DTR;
555 		if (sig & UART_SIG_RTS)
556 			bits |= TIOCM_RTS;
557 		if (sig & UART_SIG_DSR)
558 			bits |= TIOCM_DSR;
559 		if (sig & UART_SIG_CTS)
560 			bits |= TIOCM_CTS;
561 		if (sig & UART_SIG_DCD)
562 			bits |= TIOCM_CD;
563 		if (sig & (UART_SIG_DRI | UART_SIG_RI))
564 			bits |= TIOCM_RI;
565 		*(int*)data = bits;
566 		break;
567 	default:
568 		error = pps_ioctl(cmd, data, &sc->sc_pps);
569 		if (error == ENODEV)
570 			error = ENOTTY;
571 		break;
572 	}
573 	return (error);
574 }
575